1. Field of the Invention
The present invention relates to an electrical connection box and, in particular, to an attachment structure for a protection apparatus for breaking the supply of electrical power from an in-vehicle power supply to electrical loads in the case of maintenance of the electrical loads.
2. Description of the Related Art
Conventionally, an automobile has many electrical loads such as a radio receiver and a navigation apparatus. In particular, recently, such electrical loads in vehicles have continued to increase in number and amount. In order to satisfy such an increase in the power capacity requirements for electrical loads, a 36-V battery is also used in addition to a conventional 12-V battery in some cases.
During maintenance work of these electrical loads, the situation where voltage from the battery is still applied to the electrical loads is not preferable. Thus, in the prior art, before maintenance work of electrical loads, wires, etc., connected to the battery need to be removed in order to break the supply of electrical power to the electrical loads.
In order to resolve the problem, a protection apparatus for breaking the supply of electrical power from a battery to electrical loads in the case of maintenance of the electrical loads has been proposed to be attached in the vicinity of the battery via an attachment structure such as a connector. Such a protection apparatus is disclosed in Japanese Unexamined Patent Publication Nos. Hei 9-223439, Hei 9-147734, and Hei 9-147674.
Such a protection apparatus has been installed in an independent manner in the engine compartment. Nevertheless, with the sophistication of vehicles, the engine compartment has been recently equipped with an increasing number of components. This has reduced the space available for installing the protection apparatus in the engine compartment, and has thereby caused difficulty in installing the protection apparatus in the engine compartment. Further, an attachment structure is necessary for fixing the protection apparatus. This has caused an increase in costs necessary for installing the protection apparatus. Furthermore, the protection apparatus is installed intact in the engine compartment. This has caused difficulty in ensuring water proofing properties of the protection apparatus.
The invention has been devised in consideration of the above-mentioned problems. A first object of the invention is to provide an electrical connection box capable of installing a protection apparatus securely. A second object of the invention is to provide an electrical connection box capable of reducing costs necessary for installing the protection apparatus. A third object of the invention is to provide an electrical connection box capable of ensuring the waterproofing properties of the protection apparatus.
In order to achieve the above object, the first aspect of the invention is an electrical connection box comprising a protection apparatus attachment section for accommodating a protection apparatus which includes a fixed member attached to a box main body and a movable member attached to said fixed member in an attachable and detachable manner, and which when said movable member is detached from said fixed member, breaks the supply of electrical power from an in-vehicle power supply to an electrical load.
The second aspect of the invention is an electrical connection box according to the first aspect of the invention, wherein a bus bar for engaging with an electrically conductive member provided in said electrical connection box and thereby electrically connecting said in-vehicle power supply to a discharge resistor is provided in a protruded manner on an outer side surface of said fixed member.
The third aspect of the invention is an electrical connection box according to the first or second aspect of the invention, wherein said protection apparatus attachment section is composed of a protection apparatus attachment recess for accommodating said protection apparatus.
The fourth aspect of the invention is an electrical connection box according to the third aspect of the invention, wherein a lock receiving section is provided on an inner side surface of said protection apparatus attachment recess and a locking section for locking into said lock receiving section is provided on an outer side surface of said fixed member.
The xe2x80x9coperationxe2x80x9d of the invention is described below.
In the first aspect of the invention, a protection apparatus is installed in an electrical connection box. Accordingly, even when no space is available for installing a protection apparatus inside an engine compartment, the protection apparatus can be installed easily. The protection apparatus is attached to a protection apparatus attachment section. This avoids the necessity of an attachment structure which is otherwise to be fabricated separately from the electrical connection box so as to fix the protection apparatus. Thus, costs necessary for installing the protection apparatus are reduced. Further, the protection apparatus is accommodated in the electrical connection box. This improves the water proofing properties of the protection apparatus.
In the second aspect of the invention, a bus bar is engaged with an electrically conductive member provided in the electrical connection box, whereby the protection apparatus is attached to the electrical connection box. Thus, in comparison with the case where the bus bar is bolted in order to attach the protection apparatus to the electrical connection box, the attachment work of the protection apparatus is carried out efficiently. Further, no structure for bolting is necessary in the protection apparatus attachment section and the bus bar. This reduces the number of components necessary for attaching the protection apparatus to the electrical connection box. Thus, in turn, costs necessary for attaching the protection apparatus to the electrical connection box are reduced.
In the third aspect of the invention, a protection apparatus is installed in the state accommodated in a protection apparatus attachment recess, whereby only a small portion of the protection apparatus protrudes from the box main body. This permits downsizing of the electrical connection box. At that time, the protection apparatus is supported not only on the bottom surface but also in the side surfaces by the protection apparatus attachment recess. This improves the attachment strength of the protection apparatus. Further, external force seldom acts directly on the protection apparatus. This prevents the protection apparatus from being detached by an external force. Thus, the electric connection between the protection apparatus and the electrical connection box is securely maintained, whereby electrical power is stably supplied from an in-vehicle power supply to an electrical load. Further, only a small portion of the protection apparatus is exposed. This improves the water proofing properties of the protection apparatus.
In the fourth aspect of the invention, a protection apparatus is fixed to the electrical connection box not only by engaging a bus bar with the electrical connection box, but also by locking a locking section into a lock receiving section. This means that a greater number of attachment sections are used between the protection apparatus and the electrical connection box. Thus, the protection apparatus is fixed to the electrical connection box more securely. The locking section contacts with the lock receiving section. This prevents the protection apparatus from shifting even when an external force, such as vibrations, acts on the protection apparatus. This prevents the protection apparatus from being detached. Thus, electrical power is stably supplied from an in-vehicle power supply to an electrical load.